package com.yixin.filter;

import com.yixin.utils.CurrentHolder;
import com.yixin.utils.JWTUtils;
import io.jsonwebtoken.Claims;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;

@Slf4j
@WebFilter("/*") // 拦截所有请求
public class TokenFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
//        Filter.super.init(filterConfig);
        log.info("LoginFilter init...");
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        // 1. 获取请求路径
        String requestURI = request.getRequestURI();
        // 2. 判断是否是登录请求，如果路径中包含/login, 则放行
        if (requestURI.contains("/login")) {
            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
        // 3. 获取请求头中的token
        String token = request.getHeader("token");
        // 4. 判断token是否存在，如果不存在，返回错误信息(401状态码)
        if (token == null || token.isEmpty()) {
            log.info("token不存在");
            response.setStatus(401);
            return;
        }
        // 5. 如果token存在，校验令牌，如果校验失败 -> 返回错误信息(401状态码)
        try {
            Claims claims = JWTUtils.parseJWT(token);
            int id = Integer.valueOf(claims.get("id").toString());
            CurrentHolder.setCurrentId(id);
            log.info("当前用户id: {}", id);
        } catch (Exception e) {
            log.info("令牌校验失败");
            response.setStatus(401);
            return;
        }

        // 6. 校验通过，放行
        log.info("令牌校验通过");
        filterChain.doFilter(servletRequest, servletResponse);

        // 7. 释放资源
        CurrentHolder.remove();
    }

    @Override
    public void destroy() {
//        Filter.super.destroy();
        log.info("LoginFilter destroy...");
    }
}
